Currently, spunlaid process (also known as polymer laid process) already became a most fast growing technology in the technical field of nonwoven manufacturing process because of advantages of simple process with high economical effect. The spunlaid nonwoven are produced from melted macromolecule polymers through extruding and stretching melted polymers to form continuous filaments as well as stacking laying for web formation so that the nonwoven fabrics of such filaments feature in good physical properties of air permeability and water absorption. Thus, such nonwoven fabrics are prevalently used in application fields of medical, sanitary, wiper, filters and so on.
Wherein, main raw materials of spunlaid process are from polypropylene (PP), polyester (PET), polyethylene (PE) and Nylon in quantity order with overall consumed quantity 96% of global total consumption. According to the survey and statistics of Association of the Nonwoven Fabrics Industry USA, which used to be International Nonwovens & Disposables Association (INDA), the marketing share for the spunlaid nonwoven already from 33.5% in 1994 (second) leaps up to 43.7% in 2009 (first) with total annual yield of 2.7 million tons. However, the wasted spunlaid nonwoven after having been used incurs a malignant impact to natural environment because they are indissoluble or un-degradable by natural environment.
Accordingly, most countries stipulate relevant technical regulations about flammability for textile products in succession so that importing and marketing of such textile products against these technical regulations is prohibited. Moreover, demand of the fireproof or flame retarding nonwoven products is constantly increasing such as industrial nonwoven, household decorating fabric and drapes, which are all required to have rather flame retarding capability so that they can avoid accidents. However, for those spunlaid nonwoven textile products employed polypropylene (PP), polyester (PET), polyethylene (PE) and Nylon as raw materials mentioned above, they all belong to indissoluble or un-degradable fiber. Therefore, their wastes are also indissoluble or un-degradable, which will incur substantially harmful burden to natural environment.
In view of these foregoing facts, how to produce expected nonwoven from natural cellulose fibers, namely dissoluble fiber of degradable feature, with long-acting flame retarding capability via special cross-linking reaction under preset process conditions becomes a critical and urgent demand.